Baseboard-type gas heater



Nov. 19, 1963 w. o. WARE ETAL 3,111,122

BASEBOARD-TYPE GAS HEATER Filed Nov. 20, 1961 INVENTORS WILLARD O. WAREROBERT C. WARE BY Wm AGENT L. ,2 .5 Fan- 3,l.ll,ll22 Patented Nov. 19,1953 3,111,122 EASEBtlARD-TYPE GAS HEATER Willard 0. Ware, Racine, Wisand Robert C. Ware,

@lean, N.Y., assignors to Lear Siegler line, a corporation of DelawareFiled Nov. 2t), 1961, Ser. No. 153,437 7 Claims. (Cl. 126-85) Thisinvention relates to gas-tired space heaters, and more particularly isconcerned with heaters having a socalled sealed-in combustion chamber,i.e., heaters in which the products of combustion or flue gases do notmix with the air in the room in which the heater is disposed.

In spite of the extensiveness of the art relating to gasfired spaceheaters, no unit has previously been developed to compete successfullywith low, horizontally elongated heaters which operate on electricallygenerated heat or on steam or on circulating hot water. This low form ofheater is commonly referred to as the baseboard type and is extremelypopular because it is relatively inconspicuous and has a modern low,compact appearance. The only gas-fired heaters that have been marketedthus far are comparatively high and bulky so that they are unacceptableto a purchaser looking for a baseboard type of heater.

it is a principal object of this invention to provide a gas-ired spaceheater of the low, compact baseboard type.

Another important object is to utilize more eiilciently the combustionheat generated in the heater.

These and other objects and advantages of the invention will be evidentfrom the description which follows.

in accordance with the invention, a low, horizontally elongated box orchamber made of sheet metal has therein a generally horizontal bafflepartially dividing the chamber into a lower air supply zone and an uppercombustion zone, these two zones merging together beyond the edge of thebafde. A gas burner is disposed within the box adjacent the edge of thebafiie in the region where the air supply and combustion zones merge. Aduct connected to the back of the box supplies air through an opening inthe back below the bafile and horizontally spaced from the burner.Another duct disposed in nested relation with the air supply duct isalso connected to the back of the chamber and communicates with theupper combustion zone through another opening in the back of the boxabove the generally horizontal baffle and substantially in verticalalignment with the opening below the baffle. Thus, there is provided aheater in which air entering the air supply duct flows through the loweropening in the back or" the box and laterally below the generallyhorizontal bafile, mixes with and supports combustion of the gas exitingfrom the burner, and the resulting hot combustion products or flue gasesmove laterally above the battle in countercurrent heat exchange relationwith the aforesaid incoming air and discharge through the opening abovethe baffle as well as through the flue duct connected thereto into theatmosphere.

The lateral flows of incoming air and outgoing flue gases on oppositesides of the generally horizontal bafile within the metal box not onlypermit the heater to have a low, horizontally elongated form but alsoachieve effective countercurrent heat exchange across the batlle fromthe hot flue gases to the incoming air so that less heat is Wasted withthe flue gases vented from the heater. This countercurrent heat exchangefrom the flue gases to the incoming air is further carried out in thenested ducts connected to the back of the metal box. For this purpose,the inner duct is made of metal of good thermal conductivity and this isalso desirable for the walls of the metal box and the battle between theair supply and combustion zones therein.

In its optimum form for compactness, effectiveness and versatility, theheater of this invention is provided with two burners disposed at theopposite ends of the metal box or chamber while the nested ducts forincoming air and outgoing flue gases communicate with the box at a pointbetween the two burners. A balfle along the verlcal centerline of thenested ducts extends from the top to the bottom of the metal box andthus splits the incoming air into two streams flowing in oppositedirections to the separated burners. The two stream or" fiue gases fromthe two burners move toward each other until the vertical baffle ellectseach stream into the flue duct connected to the back of the metal boxabove the generally horizontal bafile.

This twin arrangement of burners in the heater of this invention isespecially advantageous because it has unique versatility, compactnessand effectiveness. Since either burner alone or both burners may beoperated from time to time depending on weather conditions and thedesired amount of warmth, the twin-type heater is obviously versatile inpermitting a very wide range of heating capacity. Yet, compactness isnot sacrificed because the metal box is not made higher to accommodate asecond burner. The baseboard-like box is merely longer when tWo burnersare used and this elongated form is more effective in heating a roomsince heat is given off more uniformly to a wider area of the room.

For a clearer understanding of the invention, reference is now made tothe accompanying drawings of which:

FIG. 1 is a front elevation of a preferred embodiment of the invention,the front wall of the heater having been removed to show the internalstructure of the heater; and

FIG. 2 is a sectional plan view of the same heater, taken along the line22 of FIG. 1 which, in turn, is a sectional view taken along the linel-1 of FIG. 2.

FIG. 1 shows a twin burner heater having a horizontally elongatedchamber it made of sheet metal and provided with a generally horizontalinternal baffie 11 and a vertical internal bafile 12. Baflles Ill and 12which intersect one another divide chamber 19 into four zones, two uppercombustion zones C and C, and two lower air supply zones A and A. Whilevertical batlle 12 extends from the door 13 to the ceiling M of chamberit), baffle 11 ends a distance from the opposite sides 15 of chamber in.

A gas burner 16 projects inwardly into chamber 10 from each side 15 thefull distance from side 15 to the terminal edge of bafiie it. The backwall 17 of chambet it) has an arcuate cutout 1? below battle it andextending on both sides of vertical bafiie 12. As will presently beexplained, air enters supply zones A and A through cutout 18. Back wall17 also has a circular opening 19 above baflle l1 and extending onopposite sides of vertical bafrle 12. Hot line gases may thus flow fromzones C and C through opening 19.

Brackets 2%) are attached to chamber 10 so that chamher it? may befastened with screws or the like to a wall of the room in which theheater of this invention is to be used. Preferably, brackets 2@ supportchamber It) in spaced relation to the wall for the purpose of permittingair to flow up between the wall and back 17 of chamber 19. In this way,not only does the air in the room warm up more rapidly because back 17is utilized as heat transfer surface, but also the wall is protectedfrom excessive temperatures resulting in chamber Before chamber ismounted on a wall, it is advisable to place a metal sheet like aluminumfo l against the wall directly in back of chamberdil as furtherprotection for the wall and as a reflective panel to minimize the lossof heat through the wall.

A cylindrical duct 21 is connected to the back 1'7 of chamber 10 andcommunicates with cutout 18. Another cylindrical duct 22 of smallerdiameter is disposed within duct 21 and is connected to opening 19.Thus, air flowing through the generally annular space between ducts 21and 22 discharges through cutout 18 into supply zones A and A, supportsthe combustion of gas fed by burners 15, and the resulting flue gasesflow through zones C and C, escaping through opening 19 and duct 22associated therewith.

Air duct 21 has a length sufiicient to pass through the wall of the roomin order to convey outdoor air to supply zones A and A of chamber 10.Flue duct 22 is a little longer than duct 21 because otherwise fluegases discharging from duct 22 would tend to flow back into air duct 21whereas fresh air is desired for efiicient combustion of gas supplied toburners 16. To minimize further the return of flue gases to the heater,the discharge end of duct 22 is desirably provided with diffuser rings23 and 24 and a cap disc 25, all of these elements being held togetherin spaced relation to one another by posts as. Cap 25 serves to preventrain or snow from being blown into duct 22 during a storm.

The end of air duct 21 is generally flush With the exterior surface ofthe building. A collar ring 27 may be placed over the end of duct 21 andin contact with the exterior surface of the building. A wire screen 28or the equivalent forms a cylindrical sleeve around duct 22, extendingfrom collar 27 to ring 23, and prevents insects, leaves and other flyingdebris from being drawn into the heater.

Burners 16 which may be of the ribbon or slotted or other known type forthe combustion of fuel gas are preferably mounted individually on ametal plate 29 which, in turn, is removably fastened to side 15 ofchamber 16?. Side 15 has an opening L d large enough to permit theinsertion of burner 16 into chamber 110 and plate 29 is so dimensionedas to seal up opening 3t? when burner 16 is in place and plate 29 isfastened to side 15 by bolts or the like. A gas supply spud 31 passesthrough and is attached to plate 29 to inject gas into burner 16. Ofcourse, burner 16 will have associated therewith the usual accessoriessuch as a pilot light, pilot safety valve and main control valve that iseither manually operable or automatically responsive to a thermostat.Such devices for use with gas space heaters are well known and henceneed no further description.

As is customary, the heater of the invention is hidden from view afterinstallation by a cover case that is commonly called a radiatorenclosure. Such a case or enclosure will ordinarily have only a front,top and two side panels. The floor of the room and the wall againstwhich the enclosure is placed act as the remaining panels of theenclosure. The front panel is spaced from the floor or is slotted nearthe floor for the entry of room air which then flows up around theheater, particularly along the front and back walls of the heater. Agrill or slots in the top panel and/ or near the top of the front panelprovide a vent so that the rising heated air may exhaust from theenclosure back into the room.

The low, compact form of the heater of this invention is bestappreciated by consideration of typical dimensions. The height, measuredas the distance between the top and bottom walls of the metal box, isdesirably in the range of about 10 to 18 inches. The depth, i.e., thespace between the front and back walls of the box, is only from about 3to 6 inches. The length of the twin burner box varies from approximately4 to 8 feet, while the single burner box is only about one-half as long.The outer duct has a diameter of the order of 6 inches and the innerduct is about 3 inches in diameter.

The heat output of the heater of this invention will depend on the sizeof the burners used. Each burner may be chosen to have a heatingcapacity in the approximate range of 5,000 to 15,000 Btu. per hour.

Many variations and modifications of the disclosed heater will beevident to those skilled in the art without departing from the spirit orscope of the invention. For instance, the generally horizontal baiiiemay slope from the duct connections to the burner rather than have thestep-like form shown in FIG. 1. Where the heater has a single burner atone longitudinal end and the nested ducts are connected to the metal boxnear the opposite end, the vertical bafile is omitted. Furthermore,while the nested ducts are arranged in FIGS. 1 and 2 to have the fluegases flow through the inner duct, they may be rearranged so thatincoming air will fiow through the inner duct. For this rearrangement,the position of the inner duct and its opening in the back of the box isdropped within the outer duct so that the inner duct will communicatewith the lower air supply zone in the metal box and at the same time theopening in the back of the box for the outer duct is moved to a positionabove the bafile extending over the air supply zone. Additionally, thenested ducts may be rectangular in cross-section rather thancylindrical. Accordingly, only such limitations should be imposed on theinvention as are indicated by the appended claims.

What is claimed is:

1. A baseboard-type space heater which comprises a low, horizontallyelongated box having the walls thereof made of sheet metal, a gas burnerdisposed in said box adjacent a longitudinal end of said box, a pair ofnested ducts longitudinally spaced from said burner and connected to theback wall of said box, a bafiie in said box extending across the fullwidth of said box from said nested ducts to a point contiguous to saidburner, said baffle forming an upper combustion zone and a lower airsupply zone on the opposite sides of said bafile, an air inlet openingin said back wall below said bafile and in communication with one ofsaid nested ducts, and a flue gases outlet opening in said back wallabove said baflle and in communication with the other of said nestedducts.

2. The space heater of claim 1 wherein the flue gases outlet opening isin communication with the inner duct of the nested ducts.

3. The space heater of claim 1 wherein the gas burner is mounted by itsgas inlet end on a plate and said plate is removably fastened to alongitudinal end of the box.

4. The space heater of claim 1 wherein a second gas burner is disposedin the box adjacent the longitudinal end thereof opposite thelongitudinal end having the other gas burner disposed adjacent thereto,the pair of nested ducts is connected to the back wall of said box at anintermediate point between said burners, and the bathe also extendsacross the full width of said box from said nested ducts to a pointcontiguous to said second burner.

5. A baseboard-type space heater which comprises a low, horizontallyelongated box having the walls thereof made of sheet metal, a gas burnerdisposed in said box adjacent each longitudinal end of said box, a pairof nested ducts connected to the back wall of said box at anintermediate point between said burners, a bafiie in said box extendingacross the full width of said box between points contiguous to saidburners and forming an upper combustion zone and a lower air supply zoneon opposite sides of said baftle, an air inlet opening in said back wallbelow said bafile and in communication with one of said nested ducts, aflue gases outlet opening in said back wall above said bafile and incommunication with the other of said nested ducts, and a vertical bafilein said box extending across the full width of said box from the top tothe bottom of said box and substantially aligned with the centerline ofsaid nested ducts.

6. The space heater of claim 5 wherein the flue gases outlet opening isin communication with the inner duct of the nested ducts.

7. The space heater of claim 5 wherein each gas burner is mounted by itsgas inlet end on a plate and said plate is removably fastened to alongitudinal end of the box.

References Cited in the file of this patent UNITED STATES PATENTSRichardson :Sept. 19, 1882 Baird et a1 Mar. 2, 1937 Barnes Oct. 31, 1944Lilly et a1 Nov. 21, 1950 Cartter Aug. 21, 1956 Moran Oct. 29, 1957

1. A BASEBOARD-TYPE SPACE HEATER WHICH COMPRISES A LOW, HORIZONTALLYELONGATED BOX HAVING THE WALLS THEREOF MADE OF SHEET METAL, A GAS BURNERDISPOSED IN SAID BOX ADJACENT A LONGITUDINAL END OF SAID BOX, A PAIR OFNESTED DUCTS LONGITUDINALLY SPACED FROM SAID BURNER AND CONNECTED TO THEBACK WALL OF SAID BOX, A BAFFLE IN SAID BOX EXTENDING ACROSS THE FULLWIDTH OF SAID BOX FROM SAID NESTED DUCTS TO A POINT CONTIGUOUS TO SAIDBURNER, SAID BAFFLE FORMING AN UPPER COMBUSTION ZONE AND A LOWER AIRSUPPLY ZONE ON THE OPPOSITE SIDES OF SAID BAFFLE, AN AIR INLET OPENINGIN SAID BACK WALL BELOW SAID BAFFLE AND IN COMMUNICATION WITH ONE OFSAID NESTED DUCTS, AND A FLUE GASES OUTLET OPENING IN SAID BACK WALLABOVE SAID BAFFLE AND IN COMMUNICATION WITH THE OTHER OF SAID NESTEDDUCTS.